This is my entry in Phoenix Phrenzy, showing off what Phoenix and LiveView can do.

This is a simple Flight Simulator written in Elixir. The flight simulation takes place completely on the server side, where Phoenix Live View sends DOM updates over a websocket at appoximately 30fps (1 tick every ~30ms).

Every client browser will get their own world with your very own plane in it, so enjoy flying around Sydney (you'll start on the main runway of Sydney International airport).

Have fun!

• wasd or Arrow keys controls the planes' roll and pitch
  • up or w points the plane down toward the ground
  • down or s points the plane up into the air
  • left/right or a/d banks left and right
• ,/. turns the rudder left / right (yaw control - useful for taxiing on a runway)
• -/= increase / decrease speed
• Esc reset the simulation
• Space partially restore the plane to level flight

• The Artificial Horizon and Compass are rendered using hand-written SVG which is updated directly by Live View.
• The Map is implemented using Leaflet, a JS interactive mapping library https://leafletjs.com/
• The 3D Cockpit View is implemented using the ESRI library and the ArcGIS SDK https://developers.arcgis.com/javascript/latest/api-reference/esri-views-SceneView.html
• Both the Map and Cockpit view are updated using Live View Hooks which runs JS functions on DOM updates from the server

• It requires keyboard input to control the plane, so this probably won't work well on mobile devices (at least I haven't tested it)
• This is running on a tiny free tier Gigalixir deployment so if lots of people are using this, then it's going to not work that well. That said it's Elixir and it'll probably handle quite a lot of planes before crashing and burning ;)
• If you want to experience it super smooth then please run it locally to spare some bandwidth
• I tried getting the 3d camera to tilt but it wouldn't point up reliably, and often flipped upside down and be generally janky so our view stays level
• Don't fly too close to the ground as the 3d view doesn't react that well when you run into hills and mountains, but it's kind of fun.

Bug reports and PRs welcome!

This app is the starting point of building the Ground Station application for the UAV Challenge 2020 (https://uavchallenge.org/medical-rescue/). For this challenge, the BEAM UAV team will be attempting to complete the challenge using 2 drones and controlling them with as much Elixir and the BEAM for the software components as possible.

I wrote the Flight Simulator so this would be a bit more interactive and fun for a more general audience, as well as showing off the power and simplicity of Phoenix Live View.

Special thanks to Robin Hilliard for the motivation to build this and some guidance around simplifying the maths of the simulator. Also thanks to David Parry and Rufus Post for moral support.

Lastly I really appreciate all the hard work that's gone into Live View, it's an amazing technology that we'll hopefully see a lot more of in the coming years. So thanks Chris McCord and Jose Valim!

Fork this repo and start build an application! See Phoenix Phrenzy for details.

Note: for development, you'll need Elixir, Erlang and Node.js. If you use the asdf version manager and install the relevant plugins, you can install the versions specified in .tool-versions with asdf install.

How you deploy your app is up to you. A couple of the easiest options are:

• Heroku (instructions)
• Gigalixir (doesn't limit number of connections)

To start your Phoenix server:

• Install dependencies with mix deps.get
• Create and migrate your database with mix ecto.setup
• Install Node.js dependencies with cd assets && npm install
• Start Phoenix endpoint with mix phx.server

Now you can visit localhost:4000 from your browser.

Ready to run in production? Please check our deployment guides.

• Official website: http://www.phoenixframework.org/
• Guides: https://hexdocs.pm/phoenix/overview.html
• Docs: https://hexdocs.pm/phoenix
• Mailing list: http://groups.google.com/group/phoenix-talk
• Source: https://github.com/phoenixframework/phoenix